898 resultados para wild reservoirs
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INTRODUCTION: Deforestation, uncontrolled forest, human population migration from endemic areas, and the large number of reservoirs and wild vectors naturally infected by Trypanosoma cruzi promote the endemicity of Chagas disease in the Amazon region. METHODS: We conducted an initial serological survey (ELISA) in a sample of 1,263 persons; 1,095 (86.7%) were natives of the State of Amazonas, 666 (52.7%) were male, and 948 (75.1%) were over 20 years old. Serum samples that were found to be reactive, indeterminate, or inconclusive by indirect immunofluorescence (IFI) or positive with low titer by IFA were tested by Western blot (WB). Serologically confirmed patients (WB) were evaluated in terms of epidemiological, clinical, ECG, and echocardiography characteristics. RESULTS: Fifteen patients had serologically confirmed T. cruzi infection, and 12 of them were autochthonous to the state of Amazonas, for an overall seroprevalence of 1.2% and 0.9% for the state of Amazonas. Five of the 15 cases were males, and the average age was 47 years old; most were farmers with low education. One patient who was not autochthonous, having originated from Alagoas, showed right bundle branch block, bundle branch block, and anterosuperior left ventricular systolic dysfunction with an ejection fraction of 54%. CONCLUSIONS: The results of this study ratify the importance of monitoring CD cases in Amazonia, particularly in the state of Amazonas.
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Introduction Hantavirus infections have been described in several regions in Brazil through seroepidemiological studies. Usually, populations are associated with rural and wild environment mainly due to close contact to species of Sigmodontinae rodents, considered hantavirus reservoirs. Methods A retrospective serosurvey was conducted to access the hantavirus seroprevalence in people living in regions affected by bovine vaccinia outbreaks. Results Sera from 53 patients were analyzed and none of them presented anti-hantavirus IgG antibodies. Conclusions This study presents an opportunity to analyze seronegativity despite close and recurrent contact with known hantavirus reservoirs. Aspects of hantavirus and bovine vaccinia emergence are also discussed.
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Visando obter informações sobre a melhor técnica de enxertia em cupuaçuzeiro (Theobroma grandiflorum (Wild ex Sprebg) Schum), são estudadas neste trabalho seis diferentes modalidades: Forket; enxertia de "placa de seringueira"; escudo; "Tê" invertido; garfagem lateral no alburno e garfagem de topo em fenda cheia. Essas técnicas foram combinadas com e sem corte prévio de 2/3 da parte apical de cada uma das folhas do material matriz (toalete). Os enxertos, foram amarrados com fita plástica e as garfagens, protegidas com sacos plásticos de polietileno transparentes. As mudas, durante todo o experimento, permaceceram em canteiros, protegidas por três telas de nylon verde, sobrepostas. Os dados evidenciaram que o uso de toalete prejudicou o pegamento, provavelmente devido a interferência no balanceamento hormonal nos enxertos. As técnicas consideradas como as melhores foram: garfagem lateral no alburno e a enxertia de placa de seringueira.
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For years, silk fibroin of a domestic silkworm, Bombyx mori, has been recognized as a valuable material and extensively used. In the last decades, new application fields are emerging for this versatile material. Those final, specific applications of silk dictate the way it has been processed in industry and research. This review focuses on the description of various approaches for silk downstream processing in a laboratory scale, that fall within several categories. The detailed description of workflow possibilities from the naturally found material to a finally formulated product is presented. Considerable attention is given to (bio-) chemical approaches of silk fibroin transformation, particularly, to its enzyme-driven modifications. The focus of the current literature survey is exclusively on the methods applied in research and not industry.
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Wild boar (Sus scrofa) and red deer (Cervus elaphus) are the main maintenance hosts for bovine tuberculosis (bTB) in continental Europe. Understanding Mycobacterium tuberculosis complex (MTC) excretion routes is crucial to define strategies to control bTB in free-ranging populations, nevertheless available information is scarce. Aiming at filling this gap, four different MTC excretion routes (oronasal, bronchial-alveolar, fecal and urinary) were investigated by molecular methods in naturally infected hunter-harvested wild boar and red deer. In addition MTC concentrations were estimated by the Most Probable Number method. MTC DNA was amplified in all types of excretion routes. MTC DNA was amplified in at least one excretion route from 83.0% (CI95 70.8-90.8) of wild ungulates with bTB-like lesions. Oronasal or bronchial-alveolar shedding were detected with higher frequency than fecal shedding (p < 0.001). The majority of shedders yielded MTC concentrations <10(3) CFU/g or mL. However, from those ungulates from which oronasal, bronchial-alveolar and fecal samples were available, 28.2% of wild boar (CI95 16.6-43.8) and 35.7% of red deer (CI95 16.3-61.2) yielded MTC concentrations >10(3) CFU/g or mL (referred here as super-shedders). Red deer have a significantly higher risk of being super-shedders compared to wild boar (OR = 11.8, CI95 2.3-60.2). The existence of super-shedders among the naturally infected population of wild boar and red deer is thus reported here for the first time and MTC DNA concentrations greater than the minimum infective doses were estimated in excretion samples from both species.
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Leishmaniasis a disease of worldwide occurrence is caused by protozoa of the Leishmania genus. In Brazil, Leishmania (Viannia) braziliensis is the main parasite responsible for the American cutaneous leishmaniasis. Main hosts of this protozoa are small wild mammals particularly marsupials and rodents. The aim of this study was to evaluate if spiny rat Proechimys guyannensis (Rodentia: Echimydae) has role in the cycle of the American cutaneous leishmaniasis caused by L. (V.) braziliensis. Thus, promastigotes (the flagellate stage) of Leishmania (Viannia) braziliensis were used to inoculate seven spiny rats (Proechimys guyannensis). After inoculated intradermal at the ear pinna, nose and plantar pad, the rats were monitored for 180 days. Tissue samples collected at 90 and 180 days from the rats proved to be negative for the presence of genetic material from the parasite. After euthanasia, the protozoa also failed to growth in culture medium containing tissue samples collected from the rats showing that there was no infection. These results fail to prove that spiny rat has a role in the cycle of the American cutaneous leishmaniasis caused by L. (V.) braziliensis.
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Mushrooms are rich sources of bioactive compounds such as phenolic acids. When ingested, these molecules have to be released from the matrix to be transformed/absorbed by the organism, so that they can exert their bioactivity. Several in vitro methodologies have been developed in order to evaluate the bioavailability of bioactive compounds. Herein, two Hericium species were analyzed for their chemical composition and antioxidant activity. Furthermore, an in vitro digestion of the mushrooms and mushroom phenolic extracts was performed, and the digested samples were also submitted to antioxidant activity evaluation in order to evaluate the bioaccessibility of the phenolic acids identified in the samples. Hericium species showed similar chemical profiles (except for tocopherols), varying only in the concentration of the compounds. The phenolic extracts revealed higher antioxidant activity than the in vitro digested samples, meaning that this process decrease the antioxidant properties of the extract/mushroom. Nevertheless, phenolic acids were found in the digested samples, meaning that those molecules are bioaccessible.
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The stem cell niche organization and dynamics provide valuable cues for the development of mimetic environments that could have potential to stimulate the regenerative process. We propose the use of biodegradable biomaterials to produce closed miniaturised structures able to encapsulate different cell types or bioactive molecules. In particular, capsules are fabricated using the so-called layer-by-layer technology, where the consecutive (nano-sized) layers are well stabilized by electrostatic interactions or other weak forces. Using alginate-based spherical templates containing cells or other elements (e.g. proteins, magnetic nanoparticles, microparticles) it is possible to produce liquefied capsules that may entrap the entire cargo under mild conditions. The inclusion of liquefied micropcapsules may be used to produce hierarchical compartmentalised systems for the delivery of bioactive agents. The presence of solid microparticles inside such capsules offers adequate surface area for adherent cell attachment increasing the biological performance of these hierarchical systems, while maintain both permeability and injectability. We demonstrated that the encapsulation of distinct cell types (including mesenchymal stem cells and endothelial cells) enhances the osteogenic capability of this system, that could be useful in bone tissue engineering applications.
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Research Article
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Los embalses constituyen reservorios de agua artificiales que se forman para brindar múltiples propósitos. La generación de energía, la provisión de agua para consumo y riego, la atenuación de crecientes y los usos recreacionales, figuran como los más destacados. La calidad del agua y el grado de eutrofización, condicionan la realización de diferentes usos con consecuencias directas e indirectas para la Salud Pública y el recurso íctico. La eutrofización es precisamente uno de los problemas más recurrentes en los embalses de la provincia de Córdoba. Las hipótesis son: 1-El incremento en la concentración de nutrientes, principalmente fósforo y nitrógeno, favorecen la producción de florecimientos algales, con consecuencias negativas sobre la sociedad y el ambiente; 2 - El estrés ambiental producto del grado de eutrofización de los embalses aumenta la susceptibilidad de Odontesthes bonariensis, situación que contribuye al desarrollo de parásitos y a la disminución de su condición corporal. Los objetivos generales del proyecto son: a) Evaluar la variabilidad temporal y espacial de la calidad del agua de tres embalses de la cuenca del río Tercero; b) Estudiar diferentes características biológicas de la ictiofauna presente. Los reservorios a estudiar son Arroyo Corto (64,57W, 32,22S; 357 ha), Río Tercero (64,38W, 32,17S; 4600 ha) y Piedras Moras (64,28W, 32,18S; 830 ha). La superficie, cantidad de tributarios y características limnológicas que presentan estos embalses son contrastantes. Se determinará de manera estacional y en diferentes sitios de muestreo de cada embalse la calidad del agua para distintos usos, a través de análisis físico-químicos y biológicos según metodología estándar, realizando mediciones in situ y en laboratorio. Se evaluará el grado de eutrofia de los reservorios a través de la concentración de nutrientes, clorofila-a y transparencia de agua. Para evaluar la distribución espacial de clorofila-a se integraran SIG-sensores remotos y se determinarán modelos geoestadísticos para predecir florecimientos algales su composición y su relación con riesgos potenciales para la salud y el recurso íctico. Se determinará la diversidad y riqueza de la ictiofauna y la abundancia poblacional (captura por unidad de esfuerzo), la condición corporal, el crecimiento y el estado sanitario del pejerrey O. bonariensis. Para ello se utilizaran artes de pesca pasivos (red de enmalle, trasmallo), activos (red de arrastre) y aparejos de pesca (espineles). Por último, se determinará la abundancia y distribución de Limnoperma fortunei en el embalse Río Tercero. Los resultados obtenidos permitirán evaluar la calidad del agua, el estado trófico y prevenir los riesgos para la salud pública y animal en una de las cuencas de alto impacto antrópico del país. Por su parte, se obtendrán datos sobre distribución, ecología y condición de la ictiofauna, permitiendo el uso sustentable del recurso pesquero. Se obtendrán herramientas que facilitarán la gestión sistémica y la toma de decisiones en el manejo del recurso agua, su saneamiento y la determinación de áreas críticas de riesgo.